The title transfer, which was witnessed by more than two dozen astronauts who flew on Discovery over the course of its 39 missions and more than 365 days in space, kicked off a four-day festival celebrating the retired orbiter's induction into the national aerospace collection at the space museum's Steven F. Udvar-Hazy Center.

"NASA and the Smithsonian signed an agreement in 1967 that has enabled the National Air and Space Museum topreserve and display the greatest icons of our nation's space history," said Gen. J.R. "Jack" Dailey, director of the museum, in a statement released Monday. "At the Udvar-Hazy Center, Discovery will be seen by millions of people in the coming years, especially children, who will become the next generation of scientists, engineers, researchers and explorers."

Discovery in, Enterprise out

Rolling up to the Udvar-Hazy Center on Thursday morning, Discovery was parked for the ceremony opposite the orbiter that made its own spaceflights possible.

Enterprise, a prototype shuttle that never flew in space but completed a series of critical approach and landing test flights in the late 1970s, had been part of the National Air and Space Museum's collection since 1985. In December 2003, it went on display inside the Udvar-Hazy Center's McDonnell Space Hangar as its centerpiece.

On Thursday, Enterprise was rolled out of the museum's hangar and displayed with Discovery nose-to-nose.

The two spaceships were then to part ways — Discovery entering the Udvar-Hazy Center for display by day's end and Enterprise heading off to an adjacent airport apron to be mated with the Shuttle Carrier Aircraft.

Enterprise will be flown to New York's John F. Kennedy (JFK) International Airport on Monday (April 23), weather permitting.

Stand-out space shuttle

"As part of the Smithsonian collection, Discovery will bring a richer perspective to the historical and scientific significance of the space shuttle program, one of our country's greatest achievements," Wayne Clough, Secretary of the Smithsonian, said in a statement.

Discovery was the first of three orbiters retired from NASA's shuttle fleet. Its final mission, STS-133, launched Feb. 24, 2011, and landed March 9.

It completed 39 missions, spent 365 days in space, orbited the Earth 5,830 times and traveled 148,221,675 miles.

Discovery was the third of NASA's orbiters to fly. A number of its missions were associated with technological and scientific achievements, including the launch of the Hubble Space Telescope into orbit in 1990 and the deployment of the Ulysses solar probe the same year.

The fleet leader, Discovery also returned the space shuttle program to flight after the losses of Challenger and Columbia in 1986 and 2003, respectively.

Discovery was the first space shuttle to visit the International Space Station and delivered its largest laboratory. The orbiter was flown by the first African American commander, Frederick Gregory, and the first U.S. female pilot, Eileen Collins, as well as by Mercury astronaut and Senator John Glenn, who at 77 returned to orbit aboard Discovery as the oldest person to fly in space.